外生菌根真菌土生空团菌种群遗传多样性与结构研究

土生空团菌Cenococcum geophilum是生态系统中广泛分布的外生菌根真菌,具有丰富的遗传多样性和重要的生态功能.为揭示土生空团菌的种群遗传多样性和结构,本研究对采集自中国10个森林地点的桦木科Betulaceae、壳斗科Fagaceae和松科Pinaceae植物根系219份样品高通量测序的土生空团菌ITS2...

Population genetic diversity and structure of ectomycorrhizal fungus Cenococcum geophilum

Cenococcum geophilum, as one of the common ectomycorrhizal fungi, is widely distributed in various ecosystems and has highly genetic diversity and important ecological function. The population genetic diversity and structure of C. geophilum were analyzed based on internal transcribed spacer 2 (ITS2) sequences of 219 root samples collected from the plants of Betulaceae, Fagaceae and Pinaceae in 10 Chinese forest sites, using high-throughput sequencing techniques. In total, 137 haplotypes (Hap_1-Hap_137) were obtained from 4 380 ITS2 sequences of C. geophilum. Of these haplotypes, Hap_1 was dominant in the plants of Betulaceae, Fagaceae and Pinaceae and occurred in all sampling sites; 48 haplotypes distributed in a few sites, and 88 haplotypes occurred only in one site. Kruskal-Wallis test showed that not host plant family but sampling site significantly affected the haplotype richness and diversity of C. geophilum. The analysis of molecular variance (AMOVA) showed that genetic differentiation was evident within each geographical population and population in each host plant family. The neighbor-joining tree based on K-2P genetic distance showed that 10 geographical populations of C. geophilum were divided into 3 groups, and genetically C. geophilum population in Fagaceae was distant from population in Betulaceae and Pinaceae. The haplotype composition of C. geophilum was conspicuously different in the 10 sampling sites and 3 plant families, and some common haplotypes showed remarkably strong preferences for site and plant family. Further revealing the ecological function of the genetic diversity of C. geophilum is needed.